The present invention relates to photonic chips and, more specifically, to structures including a waveguide arrangement and methods of fabricating a structure that includes a waveguide arrangement.
Photonic chips are capable of being used in many applications and many systems including, but not limited to, data communication systems and data computation systems. A photonic chip integrates optical components, such as waveguides, and electronic components, such as field-effect transistors, into a unified platform. Layout area, cost, and operational overhead, among other factors, may be reduced by integrating both types of components on a single photonic chip.
On-chip communication and sensing may rely on transferring optical signals through waveguides on the photonic chip to other optical components. Optical signals propagate as electromagnetic waves within waveguides using a number of different modes characterized by different properties. The transverse magnetic (TM) mode is dependent upon transverse magnetic waves in which the magnetic field vector is oriented perpendicular to the direction of propagation. The transverse electric (TE) mode is dependent upon transverse electric waves in which the electric field vector is oriented perpendicular to the direction of propagation.
Waveguides, as well as other optical components, may include cores that are fabricated from silicon nitride or single-crystal silicon. Due to relatively weak field confinement within the core, the crosstalk between adjacent waveguides and components that operate in TM modes may be significant. The existence of such crosstalk may hinder efforts to build optical components and circuits with high density.
Improved structures including a waveguide arrangement and methods of fabricating a structure that includes a waveguide arrangement are needed.